Lecture 15:Lecture 15:

Why are arthropods successful?

Why are arthropods successful?

Goals:Goals:

Assignment:Assignment: Read: Chapter 23Read: Chapter 23Websites:http://insects.tamu.edu/fieldguide/glossary.htm http://www.hollowtop.com/finl_html/finl.html http://www.ag.ohio-state.edu/~ohioline/hyg-fact/2000/2160.html http://www.antcolony.org/Army_ants.htm http://www-micro.msb.le.ac.uk/224/Parasitol.html http://www.uky.edu/Agriculture/Entomology/ythfacts/bugfood/bugfood.htm http://www.aloha.net/~smgon/triloclass.htm http://www.ucmp.berkeley.edu/diapsids/dinosaur.html http://www.ucmp.berkeley.edu/arthropoda/arthropoda.htmlhttp://www3.sk.sympatico.ca/robss/overview_htm.html http://www.earthlife.net/insects/anatomy.html http://www.earthlife.net/insects/six01.html http://www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/mi/toc.htm http://www.biophotos.com/whitten/specimens.html

Websites:http://insects.tamu.edu/fieldguide/glossary.htm http://www.hollowtop.com/finl_html/finl.html http://www.ag.ohio-state.edu/~ohioline/hyg-fact/2000/2160.html http://www.antcolony.org/Army_ants.htm http://www-micro.msb.le.ac.uk/224/Parasitol.html http://www.uky.edu/Agriculture/Entomology/ythfacts/bugfood/bugfood.htm http://www.aloha.net/~smgon/triloclass.htm http://www.ucmp.berkeley.edu/diapsids/dinosaur.html http://www.ucmp.berkeley.edu/arthropoda/arthropoda.htmlhttp://www3.sk.sympatico.ca/robss/overview_htm.html http://www.earthlife.net/insects/anatomy.html http://www.earthlife.net/insects/six01.html http://www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/mi/toc.htm http://www.biophotos.com/whitten/specimens.html

1. Define success1. Define success

2. Compare insects to other living organisms, understand what insect adaptations have contributed to their success2. Compare insects to other living organisms, understand what insect adaptations have contributed to their success

3. Relate methods of attaining success to the human race3. Relate methods of attaining success to the human race

Biological Classification Kingdom, Phylum, Class, Order, Family, Genus, Species

Biological Classification Kingdom, Phylum, Class, Order, Family, Genus, Species

Binomial Nomenclature Leptinotarsa decemlineata

Phylum ArthropodaPhylum Arthropoda

6. Bilateral symmetry6. Bilateral symmetry

5. Open circulatory system 5. Open circulatory system

2. Segmented body2. Segmented body

3. Jointed appendages 3. Jointed appendages

7. Sexual Reproduction7. Sexual Reproduction

1. Exoskeleton1. Exoskeleton

4. Double ventral nerve cord4. Double ventral nerve cord

Crustacea Sow Bug, Lobster (26,000) Aquatic, Land .2mm-200cm Crustacea Sow Bug, Lobster (26,000) Aquatic, Land .2mm-200cm

Class Common Name Environment SizeClass Common Name Environment Size

Merostomata Horseshoe Crab (5) Aquatic 3-60mmMerostomata Horseshoe Crab (5) Aquatic 3-60mm

Pycnogonida Sea Spider (500) Aquatic Marine 05 -70cm Pycnogonida Sea Spider (500) Aquatic Marine 05 -70cm

Pauropoda None (380) Soil and Leaf Mold 5-20mmPauropoda None (380) Soil and Leaf Mold 5-20mm

Symphyla None (120) Soil and Leaf Mold 2-10mmSymphyla None (120) Soil and Leaf Mold 2-10mm

Insecta Insects (1,000,000) Aquatic, Land, Air .1mm-25cmInsecta Insects (1,000,000) Aquatic, Land, Air .1mm-25cm

Diplopoda Millipede (8000) Terrestrial .1-100cmDiplopoda Millipede (8000) Terrestrial .1-100cm

Chilopoda Centipede (3,000) Terrestrial .1-100cmChilopoda Centipede (3,000) Terrestrial .1-100cm

Classes of ArthropodaClasses of Arthropoda

Class InsectaClass Insecta

6. Unique biology6. Unique biology

1. Three Body Regions1. Three Body Regions

2. Three pairs of legs2. Three pairs of legs

3. Most groups have functional wings3. Most groups have functional wings

4. One pair of antennae4. One pair of antennae

5. Tracheae respiratory system5. Tracheae respiratory system

Criteria for measuring successCriteria for measuring success

2. Current diversity2. Current diversity

1. Historically successful1. Historically successful

3. Environmental impact3. Environmental impact

Historically SuccessfulHistorically Successful1. Trilobites – 600x106 ago, fossils = hard exoskeleton1. Trilobites – 600x106 ago, fossils = hard exoskeleton

Historically SuccessfulHistorically Successful

2. Dinosaurs – 230x106 ago, first terrestrial egg

Died out 65 x 106 years ago

2. Dinosaurs – 230x106 ago, first terrestrial egg

Died out 65 x 106 years ago

Historically SuccessfulHistorically Successful

3. Brachiopods - hard shells, diverse forms, Been around 545 x 106 years 3. Brachiopods - hard shells, diverse forms, Been around 545 x 106 years

Historically SuccessfulHistorically Successful

3. Insects - 3. Insects -

                                         

        

· Oldest fossils 400 x 106 years old· Oldest fossils 400 x 106 years old

· These fossils are already well developed· These fossils are already well developed

· Hard to find good insect fossils· Hard to find good insect fossils

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Tale of the TapeTale of the Tape

Current DiversityCurrent Diversity

Environmental ImpactEnvironmental Impact

Insects have important human impacts as well:Insects have important human impacts as well:

• Transmit disease to us, our crops and our domesticated animals

• Feed on the same things we like to eat

• $$: Pollination, silk, dyes, FOOD!

• Transmit disease to us, our crops and our domesticated animals

• Feed on the same things we like to eat

• $$: Pollination, silk, dyes, FOOD!

Insects can be found in almost every ecosystem on earthInsects can be found in almost every ecosystem on earth

Insects are vital components of food websInsects are vital components of food webs

1. Insects are arguably the most successful group of animals alive1. Insects are arguably the most successful group of animals alive

3. What about mammals?!Weight? size?

3. What about mammals?!Weight? size?

2. One-celled organisms may rival insects in number, but it’s hard to tell

2. One-celled organisms may rival insects in number, but it’s hard to tell

Success? Success?

Life history strategies: The Tortoise vs. the hare

Life history strategies: The Tortoise vs. the hare

1. The Tortoise 1. The Tortoise •High survival rate, parental care,

extended individual life, offspring training

•High survival rate, parental care, extended individual life,

offspring training

2. The Hare2. The Hare

•Short lives, small size, high reproduction offsets high mortality

•Short lives, small size, high reproduction offsets high mortality

Insect adaptations that contribute to success

Insect adaptations that contribute to success

1. Exoskeleton1. Exoskeleton

2. Jointed Appendages 2. Jointed Appendages

3. Wings 3. Wings

4. Size4. Size

5. Metamorphosis5. Metamorphosis

6. Ability to escape adverse conditions6. Ability to escape adverse conditions

7. Methods of Reproduction7. Methods of Reproduction

8. Short generation time8. Short generation time

9. Specialization9. Specialization

10. Methods of solving the water problem10. Methods of solving the water problem

· Overlapping chitin plates -- like a suit of armor

· Overlapping chitin plates -- like a suit of armor

· Attachment for muscles· Attachment for muscles

Exoskeleton- Look ma, no bones!Exoskeleton- Look ma, no bones!

· Protects from damage and water loss

· Protects from damage and water loss

Jointed appendagesJointed appendagesUsually specialized for the insect’s lifestyleUsually specialized for the insect’s lifestyle

Running, jumping, grasping, swimming, diggingRunning, jumping, grasping, swimming, digging

WingsWings

•Insects have been flying for over 250 million years!

•Insects have been flying for over 250 million years!

•Give an advantage over non-flying organisms•Give an advantage over non-flying organisms

.17 mm

Size matters:Even the largest insects are smallSize matters:Even the largest insects are small

•Easier to hide•Easier to hide

•Need less food•Need less food

•Easier to disperse•Easier to disperse

Why aren’t insects gigantic?Why aren’t insects gigantic?

Insects Limited By:1. Respiratory system- Spiracles- Trachea- Air sacs

Insects Limited By:1. Respiratory system- Spiracles- Trachea- Air sacs

2. Musculo-skeletal system2. Musculo-skeletal system

http://ask.yahoo.com/ask/20011220.html

Largest Insect ever: MeganeuraLargest Insect ever: Meganeura

http://www.uky.edu/Agriculture/Entomology/ythfacts/bugfun/trivia.htm

MetamorphosisMetamorphosis

•Allows one organism to utilize multiple habitats

•Allows one organism to utilize multiple habitats

• Or to become more specialized• Or to become more specialized

Defense!!Defense!!•Flying away•Flying away

•Scaring away•Scaring away

•Brute force•Brute forceMonarch

Poisonous Viceroy

Non-poisonous

•Hiding in plain sight•Hiding in plain sight

DiapauseDiapause- A period of slow development and metabolism- A period of slow development and metabolism

- Usually due to adverse weather: cold, lack of water, etc.- Usually due to adverse weather: cold, lack of water, etc.

Aestival diapause - summerAestival diapause - summer

Hibernal diapause - winterHibernal diapause - winter

Methods of solving the water problem

Methods of solving the water problem

•Metabolic water•Metabolic water

•Condense water from the air•Condense water from the air

•Conserve water by excreting pellets of uric acid, rather than urea

•Conserve water by excreting pellets of uric acid, rather than urea

•Wax layers in cuticle•Wax layers in cuticle

Methods of reproductionMethods of reproduction

Apis melliferaThe honey beeApis melliferaThe honey bee

AphidsAphids

DragonfliesDragonflies

Tiger BeetlesTiger Beetles

Short generation timeShort generation time

The insect with the shortest known generation time is the apple grain aphid (Rhopalosiphum prunifoliae/fitchii), which can bear live young only 4.7 days after being born. Other kinds of aphids are almost as prolific, bearing live young anywhere from five to seven days after being born. Such rapid-breeding aphids are parthenogenetic. They are so prolific that when they are born they already carry the embryos of their first children.

The insect with the shortest known generation time is the apple grain aphid (Rhopalosiphum prunifoliae/fitchii), which can bear live young only 4.7 days after being born. Other kinds of aphids are almost as prolific, bearing live young anywhere from five to seven days after being born. Such rapid-breeding aphids are parthenogenetic. They are so prolific that when they are born they already carry the embryos of their first children.

Allows rapid adaptationAllows rapid adaptation

SpecializationSpecialization

EntomophagyEntomophagy

                   

                       Man eating BugsMan eating Bugs

Proverbs VI: 6Proverbs VI: 6

Go to the ant, thou sluggard; consider her ways, and be

wise.

Go to the ant, thou sluggard; consider her ways, and be

wise.